Aborto espontáneo y sangrado en las primeras etapas del embarazo

What causes bleeding in early pregnancy?

About 25 out of 100 pregnant women have a small amount of bleeding (spotting) at the time of their missed period. This is sometimes called an 'implantation bleed', because it happens when the fertilised egg implants itself in the wall of the womb (uterus). It is harmless.

The most common cause of bleeding after the time of the missed period is a miscarriage. A less common cause of bleeding in pregnancy is an embarazo ectópico

What is miscarriage?

Miscarriage is the loss of a pregnancy at any time up to the end of the 24th week of the pregnancy. A loss after this time is called a stillbirth.

More than 8 out of 10 miscarriages occur before 13 weeks of pregnancy. These are called early miscarriages. A late miscarriage is one that happens from 13 weeks to 24 weeks of pregnancy.

What is a threatened miscarriage?

It is common to have some light vaginal bleeding at some point in the first 12 weeks of pregnancy. This does not always mean a miscarriage will happen. Often the bleeding settles and the developing infant is healthy. This is called a threatened miscarriage. It is unusual to have pain with a threatened miscarriage. If the pregnancy continues, there is no harm done to the baby.

In some cases, a threatened miscarriage progresses to a miscarriage.

How common is miscarriage?

About one in five recognised pregnancies end in miscarriage. It is thought that about half of all pregnancies end in miscarriage but that half of these are so early that women may be unaware that they are pregnant.

The vast majority of women who miscarry go on to have a successful pregnancy next time.

Recurrent miscarriages (three or more miscarriages in a row) occur in about 1 in 100 women.

Miscarriage symptoms

The usual symptoms of miscarriage are:

• Vaginal bleeding.

• Lower tummy (abdominal) cramps.

The time it takes for the bleeding to settle varies. It is usually a few days but can last two weeks or more. For most women, the bleeding is heavy with clots but not severe - it is more like a heavy period. However, the bleeding can be extremely heavy in some cases.

Missed miscarriage (no symptoms)

In some cases of miscarriage, there are no symptoms. The baby stops developing and dies but remains in the womb. There is no pain or bleeding. Some women will stop experiencing pregnancy symptoms (for example, morning sickness or breast tenderness).

This type of miscarriage may not be found until a routine ultrasonido. This may be referred to by doctors as a missed miscarriage.

What causes miscarriage?

It is thought that most early miscarriages are caused by a one-off problem with the chromosomes of the developing baby (fetus) in the womb. Chromosomes are the structures that contain the genetic information inherited from the parents.

If a baby (fetus) doesn't have the correct chromosomes, it can't develop properly and so the pregnancy will end. This is usually a one-off event and rarely occurs again. Such genetic errors become more common as the mother gets older.

Miscarriage is not caused by lifting, straining, working too hard, estreñimiento, straining at the toilet, sex, eating spicy foods or taking normal exercise.

There is no evidence that waiting for a certain length of time after a miscarriage improves the chances of having a healthy pregnancy next time.

Investigations into the cause of a miscarriage are not usually carried out until after three or more miscarriages in a row. This is because most women who miscarry will not miscarry again.

Two miscarriages are more likely to be due to chance than to some underlying cause. Even after three miscarriages in a row, six women out of every ten will have a successful pregnancy next time around.

Risk factors for miscarriage

The risk of miscarriage increases with the mother's age. In women aged 20-24 approximately 9 in 100 pregnancies end in miscarriage. In women aged over 45 the risk increases to 75 in 100.

The risk of miscarriage also increases with increasing age of the father. If the father is aged over 45 there is an increased risk of miscarriage. The effect of the father's age is not as marked as that of the mother's age.

Women are also at a greater risk of having a miscarriage if they:

• Smoke. The risk increases the more cigarettes you smoke.

• Drink too much alcohol. Drinking four units of alcohol a week (one unit is half a pint of beer or a small glass of wine) has been shown to increase the risk of miscarriage.

• Use recreational drugs.

• Have had fertility problems or it has taken a long time to conceive.

• Have any abnormalities of the womb (uterus) or a weakness of the neck of the womb (the cervix).

• Have certain medical conditions (for example, lupus eritematoso sistémico, síndrome antifosfolípido. polycystic ovary syndrome, thyroid disease).

• Tener diabetes mellitus que no está bien controlado.

• Have particular infections like listeria y Sarampión alemán (rubella).

• Are underweight (BMI less than 19) or overweight (BMI over 25).

Treatment for miscarriage

Once the cause of bleeding is known, treatment options will be discussed.

Natural or expectant management

Many women now opt to 'let nature take its course'. This is called expectant management. In most cases the remains of the pregnancy are passed out through the vagina and the bleeding stops within a few days of this, although can take up to 14 days to settle.

However, if the bleeding worsens and becomes heavier or does not settle then alternative treatment may be offered. Expectant management may not be advised if there has been a previous miscarriage or if there is a bleeding disorder or any evidence of infection.

Some women prefer to have a definitive treatment rather than taking this approach.

Medicina

In some cases medical treatment for a miscarriage is suggested. This is a tablet taken either by mouth or inserted into the vagina. This medicine helps to empty the womb (uterus) and can have the same effect as an operation.

Some women experience quite severe tummy (abdominal) cramps with this treatment. It is possible to continue to bleed for up to three weeks when medical treatment is used. However, the bleeding should not be too heavy. Many women prefer this treatment because it usually means that they do not need to be admitted to hospital and do not need an operation.

An operation may be offered if the bleeding does not stop within a few days, or if the bleeding is severe.

Cirugía

If the options above are not suitable or are not successful then an operation is likely to be offered. The operation most commonly performed to remove the remains of the pregnancy is called surgical management of miscarriage (SMM). It is also sometimes called evacuation of retained products of conception (ERPC).

In this operation, the neck of the womb (the cervix) is gently opened and a narrow suction tube is placed into the womb to remove the remains of the pregnancy. This operation takes around 10 minutes.

This may be performed without the need for a general anaesthetic in some cases. This is called a manual vacuum aspiration (MVA).

There is a small risk of developing an infection after having this operation. This happens in about 2 cases out of 100. Prompt medical advice should be sought if there is a temperatura alta (fiebre), any offensive-smelling vaginal discharge or abdominal pains after a SMM. Any infection is usually treated successfully with antibióticos.

Do I need to go to hospital?

Any bleeding in pregnancy should be reported. It is important to get the correct diagnosis, as miscarriage is not the only cause of vaginal bleeding.

Most women with bleeding in early pregnancy are seen by a doctor who specialises in pregnancy - an obstetrician. This is often in an Early Pregnancy Assessment Unit at the local hospital.

Some early pregnancy units allow women to self-refer into them; others require a GP referral or referral from a doctor in the emergency department. It is usual to have an ultrasound scan. This is usually done by inserting a small probe inside your vagina. This helps to determine whether the bleeding is due to:

• A threatened miscarriage (a heartbeat will be seen inside the womb (uterus)).

• A miscarriage (no heartbeat is seen).

• Some other cause of bleeding (such as an ectopic pregnancy - see above).

Sometimes blood tests to look for the pregnancy hormone (beta-HCG) are used. If it is unclear from the ultrasound scan or blood tests whether the pregnancy is healthy or not then a repeat scan in one to two weeks is often suggested.

Women who have already had a scan confirming the baby's heartbeat and who have never had a miscarriage before may be advised that they do not need another scan. However, the early pregnancy unit will advise further on this.

Women who have had a scan confirming the presence of a heartbeat and who have had a previous miscarriage should be offered vaginal progesterone pessaries to be used until the end of the 16th week of pregnancy. This will be arranged in the early pregnancy unit.

Mental health impact of miscarriage

Many women and their partners find that miscarriage is distressing. You may have feelings of:

• Choque.

• Duelo

• Depresión.

• Guilt.

• Loss.

• Anger.

These feelings are common. It is best not to bottle up feelings but to discuss them as fully as possible with partner, friends, a healthcare professional or anyone else who can listen and understand.

As time goes on, the sense of loss usually becomes less. However, the time this takes varies greatly. Pangs of grief sometimes recur out of the blue. The time when the baby was due to be born may be particularly sad. The Miscarriage Association (see below for details) can offer support.